A NOVEL ONE-DIMENSIONAL CYANO-BRIDGED CHAIN COMPLEX [Gd(DMF)4(H2O)2Mn(CN)6 · H2O] n : SYNTHESIS,CRYSTAL STRUCTURE AND MAGNETOCHEMISTRY

Abstract

DMF (dimethylformamide) reacts with Gd(NO₃)₃6H₂O and K₃Mn(CN)₆ to afford a novel cyano-bridged complex [Gd(DMF)₄(H₂O)₂Mn(CN)₆] · H₂O] _n . The crystal structure of the complex (abbreviated as GdMn) has shown that it has a novel one-dimensional chain structure. The complex crystallizes in space group P2₁/c with a = 13.004(2), b = 12.762(2), c = 19.160(4) Å, β = 109.51(3)°, V = 2997.2(9) Å, D_x = 1.584 Mgm^?3, Z = 4. Variable temperature (1.5–300K) magnetism shows there exists weak antiferromagnetic interaction between Gd and Mn atoms across the cyano bridge.     

Synthesis,Crystal Structure Determination from X‐Ray Powder Diffractometry and Vibrational Spectroscopic Properties of Mg[N(CN)2]2 · 4 H2O

Magnesium dicyanamide tetrahydrate Mg[N(CN)₂]₂ · 4 H₂O was synthesized by aqueous ion exchange starting from Na[N(CN)₂] and Mg(NO₃)₂ · 6 H₂O. The crystal structure was solved and refined on the basis of powder X‐ray diffraction data (P2₁/c, Z = 2, a = 737.50(2), b = 732.17(1), c = 971.67(2) pm, β = 98.074(1)°, wR_p = 0.059, R_p = 0.046, R_F = 0.075). In the crystal there are neutral complexes [Mg[N(CN)₂]₂(H₂O)₄] which are only connected via hydrogen bonds. Above 40 °C the tetrahydrate decomposes into anhydrous Mg[N(CN)₂]₂.     

Crystal Structures of [Mn2(H2O)4(phen)2(C4H4O4)2] · 2 H2O and [Mn(phen)2(H2O)2][Mn(phen)2(C4H4O4)](C4H4O4) · 7 H2O

Reactions of 1,10‐phenanthroline monohydrate, Na₂C₄H₄O₄ · 6 H₂O and MnSO₄ · H₂O in CH₃OH/H₂O yielded a mixture of [Mn₂(H₂O)₄(phen)₂(C₄H₄O₄)₂] · 2 H₂O ( 1 ) and [Mn(phen)₂(H₂O)₂][Mn(phen)₂(C₄H₄O₄)](C₄H₄O₄) · 7 H₂O ( 2 ). The crystal structure of 1 (P1 (no. 2), a = 8.257(1) Å, b = 8.395(1) Å, c = 12.879(2) Å, α = 95.33(1)°, β = 104.56(1)°, γ = 106.76(1)°, V = 814.1(2) ų, Z = 1) consists of the dinuclear [Mn₂(H₂O)₄(phen)₂(C₄H₄O₄)₂] molecules and hydrogen bonded H₂O molecules. The centrosymmetric dinuclear molecules, in which the Mn atoms are octahedrally coordinated by two N atoms of one phen ligand and four O atoms from two H₂O molecules and two bis‐monodentate succinato ligands, are assembled via π‐π stacking interactions into 2 D supramolecular layers parallel to (101) (d(Mn–O) = 2.123–2.265 Å, d(Mn–N) = 2.307 Å). The crystal structure of 2 (P1 (no. 2), a = 14.289(2) Å, b = 15.182(2) Å, c = 15.913(2) Å, α = 67.108(7)°, β = 87.27(1)°, γ = 68.216(8)°, V = 2934.2(7) ų, Z = 2) is composed of the [Mn(phen)₂(H₂O)₂]²⁺ cations, [Mn(phen)₂(C₄H₄O₄)] complex molecules, (C₄H₄O₄)^2– anions, and H₂O molecules. The (C₄H₄O₄)^2– anions and H₂O molecules form 3 D hydrogen bonded network and the cations and complex molecules in the tunnels along [001] and [011], respectively, are assembled via the π‐π stacking interactions into 1 D supramolecular chains. The Mn atoms are octahedrally coordinated by four N atoms of two bidentate chelating phen ligands and two water O atoms or two carboxyl O atoms (d(Mn–O) = 2.088–2.129 Å, d(Mn–N) = 2.277–2.355 Å). Interestingly, the succinato ligands in the complex molecules assume gauche conformation bidentately to chelate the Mn atoms into seven‐membered rings.     

Hydrate isomerism in [Cu(en)2(H2O)1.935]2[Fe(CN)6]·4H2O

The title compound, bis[di­aqua­bis­(ethyl­enedi­amine‐κ²N,N′)copper(II)­] hexa­cyano­iron(II) tetrahydrate, [Cu(C₂H₈N₂)₂(H₂O)_1.935]₂[Fe(CN)₆]·4H₂O, was crystallized from an aqueous reaction mixture initially containing CuSO₄, K₃[Fe(CN)₆] and ethyl­enedi­amine (en) in a 3:2:6 molar ratio. Its structure is ionic and is built up of two crystallographically different cations, viz. [Cu(en)₂(H₂O)₂]²⁺ and [Cu(en)₂(H₂O)_1.87]²⁺, there being a deficiency of aqua ligands in the latter, [Fe(CN)₆]⁴⁻ anions and disordered solvent water mol­ecules. All the metal atoms lie on centres of inversion. The Cu atom is octahedrally coordinated by two chelate‐bonded en mol­ecules [mean Cu—N = 2.016 (2) Å] in the equatorial plane, and by axial aqua ligands, showing very long distances due to the Jahn–Teller effect [mean Cu—O = 2.611 (2) Å]. In one of the cations, significant underoccupation of the O‐atom site is observed, correlated with the appearance of a non‐coordinated water mol­ecule. This is interpreted as the partial contribution of a hydrate isomer. The [Fe(CN)₆]⁴⁻ anions form quite regular octahedra, with a mean Fe—C distance of 1.913 (2) Å. The dominant intermolecular interactions are cation–anion O—H⋯N hydrogen bonds and these inter­actions form layers parallel to (001).     

Low‐dimensional compounds containing cyano groups. VI.

The title compound, [Cu₂(C₄H₁₂N₂)₂{Ag(CN)₂}₄(NH₃)]·2H₂O or [Ag₄Cu₂(CN)₈(C₄H₁₂N₂)₂(NH₃)]·2H₂O, contains two crystallographically different Cu^II atoms lying on twofold axes. The first Cu atom is hexacoordinated in the form of an elongated tetragonal bipyramid and is part of a plane in which Cu atoms are connected by two bridging di­amino­butane mol­ecules [Cu—N = 2.033 (4) Å] and two di­cyano­argentate anions [Cu—N = 2.622 (6) Å]. The ammine ligand stands perpendicular to this plane [Cu—N = 2.011 (6) Å] in a trans position to it. Another [Ag(CN)₂]⁻ anion connects the hexacoordinated Cu atom [Cu—N = 1.997 (8) Å] with the second Cu atom [Cu—N = 2.026 (7) Å], which is pentacoordinated in the form of a slightly distorted trigonal bipyramid by two monodentate di­cyano­argetate anions [Cu—N = 2.040 (5) Å]. The axial positions are occupied by two bridging di­amino­butane mol­ecules [Cu—N = 2.011 (4) Å] that connect the Cu atoms into chains parallel to the above plane. The water mol­ecules remain uncoordinated and thus a unique combination of two‐ and one‐dimensional structures is formed.     

Synthesis and Crystal Structure of [Cu2(H2O)2(phen)2(OH)2][Cu2(phen)2(OH)2(CO3)2] · 10 H2O with phen = 1,10‐phenanthroline

The blue copper complex [Cu₂(H₂O)₂(phen)₂(OH)₂][Cu₂(phen)₂(OH)₂(CO₃)₂] · 10 H₂O, which was prepared by reaction of 1,10‐phenanthroline monohydrate, CuCl₂ · 2 H₂O and Na₂CO₃ in the presence of succinic acid in CH3OH/H₂O at pH = 13.0, crystallized in the triclinic space group P1 (no. 2) with cell dimensions: a = 9.515(1) Å, b = 12.039(1) Å, c = 12.412(2) Å, α = 70.16(1)°, β = 85.45(1)°, γ = 81.85(1)°, V = 1323.2(2) ų, Z = 1. The crystal structure consists of dinuclear [Cu₂(H₂O)₂(phen)₂(OH)₂]²⁺ complex cations, dinuclear [Cu₂(phen)₂(OH)₂(CO₃)₂]^2– complex anions and hydrogen bonded H₂O molecules. In both the centrosymmetric dinuclear cation and anion, the Cu atoms are coordinated by two N atoms of one phen ligand, three O atoms of two μ‐OH groups and respectively one H₂O molecule or one CO₃^2– anion to complete distorted [CuN₂O₃] square‐pyramids with the H₂O molecule or the CO₃^2– anion at the apical position (equatorial d(Cu–O) = 1.939–1.961 Å, d(Cu–N) = 2.026–2.051 Å and axial d(Cu–O) = 2.194, 2.252 Å). Two adjacent [CuN₂O₃] square pyramids are condensed via two μ‐OH groups. Through the interionic hydrogen bonds, the dinuclear cations and anions are linked into 1D chains with parallel phen ligands on both sides. Interdigitation of phen ligands of neighboring 1D chains generated 2D layers, between which the hydrogen bonded water molecules are sandwiched.     

Syntheses,Crystal Structures,and Thermal Behavior of Co(phen)(HL)2 and [Co2(phen)2(H2O)4L2]·H2O with H2L = Pimelic Acid

Two Co^II complexes, Co(phen)(HL)₂ ( 1 ) and [Co₂(phen)₂(H₂O)₄L₂]·H₂O ( 2 ) (H₂L = HOOC‐(CH₂)₅‐COOH), were synthesized and structurally characterized on the basis of single crystal X‐ray diffraction data. In complex 1 the Co atoms are tetrahedrally coordinated by two N atoms of one phen ligand and two O atoms of different hydrogenpimelato ligands. Through π—π stacking interactions between carboxyl group and phen ligand, the complex molecules are assembled into 1D columnar chains, which are connected by intermolecular hydrogen bonds. Complex 2 consists of the centrosymmetric dinuclear [Co₂(phen)₂(H₂O)₄L₂] molecules and hydrogen bonded H₂O molecules. The Co atoms are each octahedrally surrounded by two N atoms of one phen ligand and four O atoms from two bis‐monodentate pimelato ligands and two H₂O molecules at the trans positions. The results about thermal analyses, which were performed in flowing N₂ atmosphere, on both complexes were discussed. Crystal data: ( 1 ) C2/c (no. 15), a = 13.491(1)Å, b = 9.828(1)Å, c = 19.392(2)Å, β = 100.648(1)°, U = 2526.9(4)ų, Z = 4; ( 2 ) P1 (no. 2), a = 11.558(1)Å, b = 11.947(3)Å, c = 15.211(1)Å, α = 86.17(1)°, β = 75.55(1)°, γ = 69.95(1)°, U = 1910.3(3)ų, Z = 2.     

New Suberato‐bridged Supramolecular Layers: Crystal Structure of [Cu2(phen)2(C8H12O4)2] · 3 H2O with phen = 1,10‐phenanthroline

The reaction of CuCl₂ · 2 H₂O, 1,10‐phenanthroline (phen), suberic acid and Na₂CO₃ in a CH₃CN–H₂O solution yielded blue needle‐like crystals of [Cu₂(phen)₂(C₈H₁₂O₄)₂] · 3 H₂O. The crystal structure (monoclinic, P2₁/n, a = 10.756(2) Å, b = 9.790(2) Å, c = 18.593(4) Å, β = 91.15(3)°, Z = 2, R = 0.043, wR² = 0.1238) consists of suberato‐bridged [Cu₂(phen)₂(C₈H₁₂O₄)_4/2] layers and hydrogen bonded H₂O molecules. The Cu atoms are coordinated by two N atoms from one bidentate chelating phen ligand and three carboxyl O atoms from different suberato ligands to form distorted [CuN₂O₃] square‐pyramids with one carboxyl O atom at the apical position (d(Cu–N) = 2.017(2), 2.043(3) Å, basal d(Cu–O) = 1.936(2), 1.951(2) Å and axial d(Cu–O) = 2.389(2) Å). Two [CuN₂O₃] square‐pyramids are condensed via a common O–O edge to a centrosymmetric [Cu₂N₄O₄] dimer with the Cu…Cu distance of 3.406(1) Å indicating no interaction between Cu atoms. The resultant [Cu₂N₄O₄] dimers are interlinked by the tridentate suberato ligands to form [Cu₂(phen)₂(C₈H₁₂O₄)_4/2] layers parallel to (101). These are assembled via π‐π stacking interactions into 3D network with H₂O molecules in the tunnels extending in the [010] direction.     

Crystal structures of three complexes structurally similar to KTbW(CN)8 · 7H2O

Three complexes that crystallize into structures like KTbW(CN)₈ · 7H₂O (triclinic crystal system, space group P $ \bar 1 $ ) were structurally characterized by X-ray diffraction: KYMo(CN)₈ · 7H₂O, a = 7.6371(5), b = 9.2569(6), c = 14.4976(2) Å, α = 80.782(6)°, β = 87.644(5)°, γ = 77.645(5)°, V = 988.23(11) ų, Z = 2, ρ_calcd = 1.876 g/cm³; KHoW(CN)₈ · 7H₂O, a = 7.5887(4), b = 9.2232(5), c = 14.4479(9) Å, α = 80.709(5)°, β = 87.525(5)°, γ = 77.457(5)°, V = 974.12(10) ų, Z = 2, ρ_calcd = 2.462 g/cm³; KErW(CN)₈ · 7H₂O, a = 7.6180(5), b = 9.2356(6), c = 14.4903(11) Å, α = 80.655(6)°, β = 87.492(6)°, γ = 77.557(6)°, V = 982.29(13) ų, Z = 2, ρ_calcd = 2.449 g/cm³. The coordination polyhedra of the d element atoms [M(CN)₈] (M⁴⁺ = Mo and W) are dodecahedra; the coordination polyhedra of the rare-earth metal atoms [RN₄(OH₂)₄] (R³⁺ = Y, Ho, and Er) are tetragonal antiprisms. Four bridging cyano groups are coordinated to the W/Mo and rare-earth metal atoms through the C and N atoms, respectively, to form a polymeric 3D structure involving potassium atoms. The coordination polymers can be formulated as {[K(H₂O)][R(H₂O)₄][M(CN)₈] · 2H₂O} _n (R³⁺ = Y, M⁴⁺ = Mo; R³⁺ = Ho and Er, M⁴⁺ = W).     

Four- and five-coordinate metal atoms in a supramolecular polymeric assembly of silver(I) with (4-methyl-2-quinolylthio)acetate

The coordination compound [Ag₂L₂(H₂O)₂] · ₂H₂O (I), L = C₁₂H₁₀NO₂S has been synthesized by the reaction of AgNO₃ with 4-methyl-2-quinolylthioacetic acid (HL) preliminarily neutralized with an equimolar amount of NBu₄OH. Its crystal structure has been determined, and luminescence properties have been studied. Crystals of I are monoclinic, space group C2/_c, _a = 31.239(6) Å, _b = 12.056(2) Å, _c = 16.846(3) Å, β = 122.17(3)°, V = 5370.4(2) ų, ρ_calc = 1.861 g/cm³, Z = 16. The structure is formed by two crystallographically nonequivalent silver atoms Ag(1) and Ag(2) and two tridentate bridging ligands L coordinated through the S, N, and O atoms. These atoms, together with water molecules, form the coordination environments of the metal atoms with CN = 5 and 4, respectively. The Ag⁺ ions and the tridentate ligands form infinite [Ag₄L₄]_n bands extended in the [001] direction. The presence of outer-sphere water molecules involved in O–H···O hydrogen bonding is responsible for the formation of a supramolecular framework structure. The photoluminescence spectrum of compound I shows two bands at ~450 and ~485 nm corresponding to the blue spectral range.     

Supramolecular Assemblies of Mononuclear and Polymeric Nickel(II) Glutarato Complexes via π‐π Stacking Interactions and Hydrogen Bonds: [Ni(H2O)3(phen)(C5H6O4)] · H2O and [Ni(H2O)2(phen)(C5H6O4)]

Syntheses of the sky blue complex compounds [Ni(H₂O)₃(phen)(C₅H₆O₄)] · H₂O ( 1 ) and [Ni(H₂O)₂(phen)(C₅H₆O₄)] ( 2 ) were carried out by the reactions of 1,10‐phenanthroline monohydrate, glutaric acid, NiSO₄ · 6 H₂O and Na₂CO₃ in CH₃OH/H₂O at pH = 6.9 and 7.5, respectively. The crystal structure of 1 (P 1 (no. 2), a = 14.289 Å, b = 15.182 Å, c = 15.913 Å, α = 67.108°, β = 87.27°, γ = 68.216°, V = 2934.2 ų, Z = 2) consists of hydrogen bonded [Ni(H₂O)₃‐ (phen)(C₅H₆O₄)]₂ dimers and H₂O molecules. The Ni atoms are octahedrally coordinated by two N atoms of one phen ligand, three water O atoms and one carboxyl O atom from one monodentate glutarato ligand (d(Ni–N) = 2.086, 2.090 Å; d(Ni–O) = 2.064–2.079 Å). Through the π‐π stacking interactions and intermolecular hydrogen bonds, the dimers are assembled to form 2 D layers parallel to (0 1 1). The crystal structure of 2 (P2₁/n (no. 14), a = 7.574 Å, b = 11.938 Å, c = 18.817 Å, β = 98.48°, V = 1682.8 ų, Z = 4) contains [Ni(H₂O)₂(phen)(C₅H₆O₄)_2/2] supramolecular chains extending along [010]. The Ni atoms are octahedrally coordinated by two N atoms of one phen ligand, two water O atoms and two carboxyl O atoms from different bis‐monodentate glutarato ligands with d(Ni–N) = 2.082, 2.105 Å and d(Ni–O) = 2.059–2.087 Å. The supramolecular chains are assembled into a 3 D network by π‐π stacking interactions and interchain hydrogen bonds. A TG/DTA of 2 shows two endothermic effects at 132 °C and 390 °C corresponding to the complete dehydration and the lost of phen.     

Hydroxo Bridged Dinuclear Rare Earth Complexes: Syntheses and Crystal Structures of [Ln2(phen)4(H2O)4(OH)2](NO3)4(phen)2 with Ln = Er,Lu

Reactions of phenanthroline (phen) and Er(NO₃)₃ · 5 H₂O or Lu(NO₃)₃ · H₂O in CH₃OH/H₂O yield [Ln₂(phen)₄(H₂O)₄(OH)₂](NO₃)₄(phen)₂ with Ln = Er ( 1 ), Lu ( 2 ). Both isostructural complex compounds crystallize in the triclinic space group P 1 (no. 2) with the cell dimensions: a = 11.257(2) Å, b = 11.467(2) Å, c = 14.069(2) Å, α = 93.93(2)°, β = 98.18(1)°, γ = 108.14(1)°, V = 1696.0(6) ų, Z = 1 for ( 1 ) and a = 11.251(1) Å, b = 11.476(1) Å, c = 14.019(1) Å, α = 93.83(1)°, β = 98.27(1)°, γ = 108.27(1)°, V = 1689.0(3) ų, Z = 1 for ( 2 ). The crystal structures consist of the hydroxo bridged dinuclear [Ln₂(phen)₄(H₂O)₄(OH)₂]⁴⁺ complex cations, hydrogen bonded NO₃^– anions and π‐π stacking (phen)₂ dimers. The rare earth metal atoms are coordinated by four N atoms of two phen ligands and four O atoms of two H₂O molecules and two μ‐OH groups to complete tetragonal antiprisms. Via two common μ‐OH groups, two neighboring tetragonal antiprisms are condensed to a centrosymmetric dinuclear [Ln₂(phen)₄(H₂O)₄(OH)₂]⁴⁺ complex cation. Based on π‐π stacking interactions and hydrogen bonding, the complex cations and (phen)₂ dimers form 2 D layers parallel to (1 0 1), between which the hydrogen bonded NO₃^– anions are sandwiched. The structures can be simplified into a distorted CsCl structure when {[Ln₂(phen)₄(H₂O)₄(OH)₂](NO₃)₄} and (phen)₂ are viewed as building units.     

Two Heteroleptic Zinc(II) Complexes: [Zn(phen)(C9H15O6)2] and [Zn2(phen)2(H2O)2(C10H16O4)2] · 3H2O

Reactions of a freshly prepared Zn(OH)_2‐2x(CO₃)x · yH₂O precipitate, phenanthroline with azelaic and sebacic acid in CH₃OH/H₂O afforded [Zn(phen)(C₉H₁₅O₄)₂] ( 1 ) and [Zn₂(phen)₂(H₂O)₂(C₁₀H₁₆O₄)₂] · 3H₂O ( 2 ), respectively. They were structurally characterized by X‐ray diffraction methods. Compound 1 consists of complex molecules [Zn(phen)(C₉H₁₅O₄)₂] in which the Zn atoms are tetrahedrally coordinated by two N atoms of one phen ligand and two O atoms of different monodentate hydrogen azelaato groups. Intermolecular C(alkyl)‐H···π interactions and the intermolecular C(aryl)‐H···O and O‐H···O hydrogen bonds are responsible for the supramolecular assembly of the [Zn(phen)(C₉H₁₅O₄)₂] complexes. Compound 2 is built up from crystal H₂O molecules and the centrosymmetric binuclear [Zn₂(phen)₂(H₂O)₂(C₁₀H₁₆O₄)₂] complex, in which two [Zn(phen)(H₂O)]²⁺ moieties are bridged by two sebacato ligands. Through the intermolecular C(alkyl)‐H···O hydrogen bonds and π‐π stacking interactions, the binuclear complex molecules are assembled into layers, between which the lattice H₂O molecules are sandwiched. Crystal data: ( 1 ) C2/c (no. 15), a = 13.887(2), b = 9.790(2), c = 22.887(3)Å, β = 107.05(1)°, U = 2974.8(8)ų, Z = 4; ( 2 ) P1¯ (no. 2), a = 8.414(1), b = 10.679(1), c = 14.076(2)Å, α = 106.52(1)°, β = 91.56(1)°, γ = 99.09(1)°, U = 1193.9(2)ų, Z = 1.     

Synthesis,Crystal Structure and Magnetic Properties of a Two-Dimensional Heterometallic Assembly ∣[Mn(salen)]∣2∣[Ni(CN)4∣·1/2H2O

A heterometallic assembly, [Mn(salen)]₂[Ni(CN)₄ ]·1/2H₂O (where salen=N, N'-ethylene-bis(salicylideneiminato)-dianion), has been prepared from the reaction of [Mn(salen)H₂O]ClO₄ ·H₂O with K₂ [Ni(CN)₄ ]·H₂O in methanol/water. The compound crystallizes in the tetragonal space group P 4/ncc with the cell dimensions of a =14.604(2) Å, c =16.949(3) Å, and Z=4. The compound assumes a two-dimensional distorted square network structure, formed from Ni―CN―Mn(salen)―NC―Ni linkages with dimensions of Ni―C = 1.867(7)Å, Mn―N - 2.312(6) Å, Mn―N―C - 163.8(6)° Ni―C―N = 178.4(6)°. The two metal atoms Ni(II) and MN(III) have square and slightly distorted octahedral arrangements, respectively. Magnetic susceptibility measurements indicate the presence of an intramolecular antiferro-magnetic interaction and gives a Mn―Mn exchange integral of ?3.2cm^?1.     

Syntheses and structures of 1d coordination polymers based on cluster anions [Re<Subscript>4</Subscript>Te<Subscript>4</Subscript>(CN)<Subscript>12</Subscript>]<Superscript>4–</Superscript> and cationic Ln<Superscript>3+</Superscript> (Ln = La,Gd) complexes with 1,10-phenanthroline

Two new porous coordination polymers based on cluster anions [Re₄Te₄(CN)₁₂]^4– and cationic Ln³⁺ (Ln = La, Gd) complexes with 1,10-phenanthroline (Рhen) are synthesized under hydrothermal conditions. The structures of the compounds are determined by X-ray diffraction analysis (CIF files CCDC 1437445 (I) and 1437446 (II)). Compound (РhenH)[{La(H₂O)₃(Рhen)₂}{Re₄Te₄(CN)₁₂}] · 1.5Рhen · 6H₂O (I) crystallizes in the space group \(P\bar 1\) (triclinic system): a = 13.322(3), b = 15.977(3), c = 18.576(4) Å, α = 71.34(3)°, β = 85.56(3)°, γ = 88.27(3)°, V = 3734.8(13) ų. Compound (PhenH)[{Gd(H₂O)₂(Phen)₂}{Re₄Te₄(CN)₁₂}] · 2Phen · 0.5H₂O (II) crystallizes in the space group C2/c (monoclinic crystal system): a = 18.146(1), b = 30.245(2), c = 13.455(2) Å, β = 97.858(2)°, V = 7315.4(1) ų. Structures I and II are based on polymer chains consisting of alternating fragments [Re₄Te₄(CN)₁₂]^4– and {Ln(H₂O) _n (Phen)₂}³⁺ (Ln = La, n = 3; Ln = Gd, n = 2) linked by the bridging CN ligands. The packings of the polymers contain extended channels due to the developed network of noncovalent interactions. The walls of the channels are formed by both hydrophilic (CN^–) and hydrophobic (Рhen) groups. The channels, whose volume is 25 and 15% for compounds I and II, respectively, are filled by disordered Phen molecules and PhenH⁺ cations, as well as by H₂O molecules.     

The Cocrystallization of the Cubic [Ta6Br12(H2O)6][CuBr2X2]·10H2O and Triclinic [Ta6Br12(H2O)6]X2·trans‐[Ta6Br12(OH)4(H2O)2]·18H2O (X = Cl,Br, NO3) Phases with the Coexistence of [Ta6Br12]2+ and [Ta6Br12]4+ in the Latter

Cubic [Ta₆Br₁₂(H₂O)₆][CuBr₂X₂]·10H₂O and triclinic [Ta₆Br₁₂(H₂O)₆]X₂·trans‐[Ta₆Br₁₂(OH)₄(H₂O)₂]·18H₂O (X = Cl, Br, NO₃) cocrystallize in aqueous solutions of [Ta₆Br₁₂]²⁺ in the presence of Cu²⁺ ions. The crystal structures of [Ta₆Br₁₂(H₂O)₆]Cl₂·trans‐[Ta₆Br₁₂(OH)₄(H₂O)₂]·18H₂O ( 1 ) and [Ta₆Br₁₂(H₂O)₆]Br₂·trans‐[Ta₆Br₁₂(OH)₄(H₂O)₂]·18H₂O ( 3 )have been solved in the triclinic space group P&1macr; (No. 2). Crystal data: 1 , a = 9.3264(2) Å, b = 9.8272(2) Å, c = 19.0158(4) Å, α = 80.931(1)?, β = 81.772(2)?, γ = 80.691(1)?; 3 , a = 9.3399(2) Å, b = 9.8796(2) Å, c = 19.0494(4) Å; α = 81.037(1)?, β = 81.808(1)?, γ = 80.736(1)?. 1 and 3 consist of two octahedral differently charged cluster entities, [Ta₆Br₁₂]²⁺ in the [Ta₆Br₁₂(H₂O)₆]²⁺ cation and [Ta₆Br₁₂]⁴⁺ in trans‐[Ta₆Br₁₂(OH)₄(H₂O)₂]. Average bond distances in the [Ta₆Br₁₂(H₂O)₆]²⁺ cations: 1 , Ta‐Ta, 2.9243 Å; Ta‐Brⁱ , 2.607 Å; Ta‐O, 2.23 Å; 3 , Ta‐Ta, 2.9162 Å; Ta‐Brⁱ , 2.603 Å; Ta‐O, 2.24 Å. Average bond distances in trans‐[Ta₆‐Br₁₂(OH)₄(H₂O)₂]: 1 , Ta‐Ta, 3.0133 Å; Ta‐Brⁱ, 2.586 Å; Ta‐O(OH), 2.14 Å; Ta‐O(H₂O), 2.258(9) Å; 3 , Ta‐Ta, 3.0113 Å; Ta‐Brⁱ, 2.580 Å; Ta‐O(OH), 2.11 Å; Ta‐O(H₂O), 2.23(1) Å. The crystal packing results in short O···O contacts along the c axes. Under the same experimental conditions, [Ta₆Cl₁₂]²⁺ oxidized to [Ta₆Cl₁₂]⁴⁺ , whereas [Nb₆X₁₂]²⁺ clusters were not affected by the Cu²⁺ ion.     

Synthesis,structures and magnetic properties of cyano- and amide-bridged FeIII-LnIII tetranuclear heterometallic clusters

Three Fe^III₂Ln^III₂ tetranuclear heterometallic clusters, [H₄LGd(H₂O)Tp*Fe(CN)₃]₂·8H₂O·2MeOH (1) and [H₄LLn(MeOH)Tp*Fe(CN)₃]₂·6MeOH·2MeCN (Ln?=?Tb and Dy for 2 and 3, respectively, H₆L = N,N′-(2,6-pyridine-dicarboxyl)-disalicylhydrazide, Tp* = hydridotris(3,5dimethylpyrazol-1-yl)-borate), were synthesized by use of the [(Tp*)Fe(CN)₃]^? unit as a metalloligand toward LnCl₃ and H₆L species. Structural analyses reveal that Fe^III and Ln^III ions in all complexes are connected to each other by one cyanide to form a heterobinuclear unit of [Ln(H₄L)][(Tp*)Fe(CN)₃], which is dimerized through Ln–N–C?=?O–Ln interaction. Magnetic susceptibility measurements show weak antiferromagnetic interactions between cyano-bridged Fe^III and Gd^III ions and amide-bridged Gd^III ions are operative. Complex 1 displays the magnetocaloric effect with ?ΔS_m^max = 12.70 J·kg^?1·K^?1 at 4.0 K for ΔH?=?7 T. No single-molecule magnetic properties are observed for 2 or 3 down to 1.8 K.     

Two Novel CuII Phenanthroline Adipato Complexes with π‐π Stacking Interactions: [Cu(phen)2(C6H8O4)] · 4.5 H2O and [(Cu2(phen)2Cl2)(C6H8O4)] · 4 H2O

The blue copper complex compounds [Cu(phen)₂(C₆H₈O₄)] · 4.5 H₂O ( 1 ) and [(Cu₂(phen)₂Cl₂)(C₆H₈O₄)] · 4 H₂O ( 2 ) were synthesized from CuCl₂, 1,10‐phenanthroline (phen) and adipic acid in CH₃OH/H₂O solutions. [Cu(phen)₂‐ (C₆H₈O₄)] complexes and hydrogen bonded H₂O molecules form the crystal structure of ( 1 ) (P1 (no. 2), a = 10.086(2) Å, b = 11.470(2) Å, c = 16.523(3) Å, α = 99.80(1)°, β = 115.13(1)°, γ = 115.13(1)°, V = 1617.5(5) ų, Z = 2). The Cu atoms are square‐pyramidally coordinated by four N atoms of the phen ligands and one O atom of the adipate anion (d(Cu–O) = 1.989 Å, d(Cu–N) = 2.032–2.040 Å, axial d(Cu–N) = 2.235 Å). π‐π stacking interactions between phen ligands are responsible for the formation of supramolecular assemblies of [Cu(phen)₂(C₆H₈O₄)] complex molecules into 1 D chains along [111]. The crystal structure of ( 2 ) shows polymeric [(Cu₂(phen)₂Cl₂)(C₆H₈O₄)_2/2] chains (P1 (no. 2), a = 7.013(1) Å, b = 10.376(1) Å, c = 11.372(3) Å, α = 73.64(1)°, β = 78.15(2)°, γ = 81.44(1)°, V = 773.5(2) ų, Z = 1). The Cu atoms are fivefold coordinated by two Cl atoms, two N atoms of phen ligands and one O atom of the adipate anion, forming [CuCl₂N₂O] square pyramids with an axial Cl atom (d(Cu–O) = 1.958 Å, d(Cu–N) = 2.017–2.033 Å, d(Cu–Cl) = 2.281 Å; axial d(Cu–Cl) = 2.724 Å). Two square pyramids are condensed via the common Cl–Cl edge to centrosymmetric [Cu₂Cl₂N₄O₂] dimers, which are connected via the adipate anions to form the [(Cu₂(phen)₂Cl₂)(C₆H₈O₄)_2/2] chains. The supramolecular 3 D network results from π‐π stacking interactions between the chains. H₂O molecules are located in tunnels.     

Assembly of a New Cyano‐bridged 4f‐3d Dimer Sm(DMSO)4‐ (H2O)3Cr(CN)6 and Crystal Structure of [K3(18‐crown‐6)3‐(H2O)4]Cr(CN)6·3H2O

A new cyano‐bridged binuclear 4f‐3d complex Sm(DMSO)₄‐(H₂O)₃Cr(CN)₆ was synthesized and characterized by single crystal structure analysis. It crystallizes in monoclinic, space group P2₁ with a=0.9367(2) nm, b = 1.3917(3) nm, c = 1.1212(2) run, β = 99.88(3)° and Z = 2. In this binuclear complex, Sm atom is eight coordinated and linked to the Cr atom by a cyano bridge. The molecules packs to form 3D structure due to the hydrogen bonds among them. [K₃(18‐C‐6)₃(H₂O)₄]Cr(CN)₆·3H₂O (18‐C‐6 represents 18‐crown‐6‐ether) that was synthesized as a byproduct in the preparation of a Gd—Cr complex is also structurally characterized. Crystal data: triclinic, space group P‐l with a = 1.0496(7) nm, b= 1.1567(14) nm, c = 1.3530(13) nm, a = 94.15(9)°, β = 96.04(8)°, γ = 95.25(9)° and Z = l. [K₃(18‐C‐6)₃(H₂O)₄]‐Cr(CN)₆·3H₂O consists of ionic [K₃(18‐C‐6)₃(H₂O)₄]³⁺ and [Cr(CN)₆]^3‐ pairs, of which the [K₃(18‐C‐6)₃(H₂O)₄]³⁺ ion is a trinuclear duster connected by water, and K atoms are eight coordinated by eight oxygen atoms of one 18‐C‐6 and two water molecules.     

Synthesis,Crystal Structure,and Magnetic Properties of {[Cu(phen)]2(C4H2O4)2} · 4.5H2O with C4H4O4 = Maleic Acid

Reaction of CuCl₂ · 2H₂O, phenanthroline, maleic acid and NaOH in CH₃OH/H₂O (1:1 v/v) at pH = 7.0 yielded blue {[Cu(phen)]₂(C₄H₂O₄)₂} · 4.5H₂O, which crystallizes in the monoclinic space group C2/c (no. 15) with cell dimensions: a = 18.127(2)Å, b = 12.482(2)Å, c = 14.602(2)Å, β = 103.43(1)°, U = 3213.5(8)ų, Z = 4. The crystal structure consists of the centrosymmetric dinuclear {[Cu(phen)]₂(C₄H₂O₄)₂} complex molecules and hydrogen bonded H₂O molecules. The Cu atoms are each square‐pyramidally coordinated by two N atoms of one phen ligand and three carboxyl O atoms of two maleato ligands with one carboxyl O atom at the apical position (d(Cu‐N) = 2.008, 2.012Å, equatorial d(Cu‐O) = 1.933, 1.969Å, axial d(Cu‐O) = 2.306Å). Two square‐pyramids are condensed via two apical carboxyl O atoms with a relatively larger Cu···Cu separation of 3.346(1)Å. The dinuclear complex molecules are assembled via the intermolecular π—π stacking interactions into 1D ribbons. Crossover of the resulting ribbons via interribbon π—π stacking interactions forms a 3D network with the tunnels occupied by H₂O molecules. The title complex behaves paramagnetically between 5—300 K, following the Curie‐Weiss law _χm(T—θ) = 0.435 cm³ · mol^—1 · K with θ = 1.59 K.